Construction of the nano-carbon connections among the carbon-coated LiFe0.8Mn0.2PO4 grains by sol-gel technique

Nano-carbon connections among carbon-coated LiFe0.8Mn0.2PO4 grains are successfully constructed using polyacrylic acid and sucrose as carbon sources by sol-gel method, which can improve the electrochemical performance of LiFe0.8Mn0.2PO4. Samples were characterised by X-ray diffraction, scanning electron microscopy and electrochemical tests. The electrochemical tests show LiFe0.8Mn0.2PO4 grains connected by nano-carbon networks obtain the discharge specific capacity of 165 mA h g−1 at 0.1 C rate and excellent rate capability. Its specific capacity reaches 122 mA h g−1 at 5 C rate. Its capacity retention at 5 C rate attains 97% cycled 100 cycles. Therefore the construction of nano-carbon networks offers an effective and convenient technique to improve the specific capacities and rate capabilities of electrode materials of low electronic conductivity.